Why Combine Sentences?
Compare these two versions of a CV line:
- I led a team. The team had eight people. It launched a mobile app. The app now has 50,000 users.
- I led an eight-person team that launched a mobile app now used by 50,000 people.
The second sentence says the same thing in half the words. Relative clauses and participle clauses are the tools that make this possible. They are essential for CVs, reports, emails and the writing sections of IELTS, CELPIP and TOEFL, where examiners look for complex sentences used accurately.
Relative Pronouns: A Quick Review
| Pronoun | Refers to | Example |
|---|---|---|
| who | people | The candidate who impressed us most was from Calgary. |
| which | things, ideas | The software which we use is outdated. |
| that | people or things (defining clauses only) | The report that you sent is excellent. |
| whose | possession | We need a supplier whose prices are stable. |
| where | places | This is the office where I started my career. |
| when | times | I remember the day when we signed the contract. |
| whom | people, as object (formal) | The manager to whom I reported was very supportive. |
Defining vs. Non-Defining Clauses
This is the most important distinction at B2.
Defining relative clauses: essential information
A defining clause tells us which one we are talking about. Without it, the sentence is incomplete or has a different meaning. There are no commas.
- Employees who work remotely must log their hours. (Only the remote employees, not all employees.)
- The laptop that I ordered hasn't arrived.
In defining clauses, you can omit the pronoun when it is the object of the clause:
- The laptop (that) I ordered hasn't arrived. (I ordered it → object → can omit.)
- The man who called was angry. (He called → subject → cannot omit.)
Non-defining relative clauses: extra information
A non-defining clause adds extra information about something already identified. It goes between commas, and you cannot use "that".
- Our CEO, who joined the company in 2019, will speak at the event.
- The Vancouver office, which opened last year, already has 40 staff.
Why the commas change the meaning
- My sister who lives in Toronto is a nurse. (I have more than one sister; this is the one in Toronto.)
- My sister, who lives in Toronto, is a nurse. (I have one sister; by the way, she lives in Toronto.)
"Which" referring to a whole clause
A non-defining which can refer to the whole previous idea:
- The project finished two weeks early, which impressed the client.
- He didn't reply to my email, which was a little strange.
Prepositions in Relative Clauses
In everyday English, the preposition goes at the end. In formal writing, it goes before whom or which:
- Informal: The person I spoke to was very helpful.
- Formal: The person to whom I spoke was very helpful.
- Formal: The policy under which refunds are issued has changed.
Participle Clauses: Shortening Relative Clauses
You can often reduce a relative clause to a participle.
Active meaning → -ing
- Candidates who apply before May 1 will get priority. → Candidates applying before May 1 will get priority.
- There's a woman who is waiting for you in reception. → There's a woman waiting for you in reception.
Passive meaning → past participle (-ed / third form)
- The report which was published yesterday shows strong growth. → The report published yesterday shows strong growth.
- Most of the products that are made in this factory are exported. → Most of the products made in this factory are exported.
Participle clauses at the start of a sentence
Participle clauses can also replace because, when, after or and:
- Having worked in sales for five years, I understand what customers need. (= Because I have worked...)
- Founded in 1998, the company now operates in twelve countries. (= It was founded in 1998, and...)
- Looking at the figures, we can see a clear trend. (= When we look at...)
Important: the subject of the participle clause must be the same as the subject of the main clause.
- Wrong:
Walking into the office, the computer was already on.(The computer was not walking!) - Correct: Walking into the office, I saw that the computer was already on.
This mistake is called a dangling participle and examiners notice it.
In Real Use: CV and Cover Letter
Having managed customer service teams in two countries, I have strong experience handling complaints that require quick decisions. In my current role, which I have held since 2022, I introduced a ticket system used by all 60 agents, which reduced response times by 35%.
Notice how each clause adds precise information without starting a new sentence.
In Exams
- IELTS Writing Task 1: The graph, which covers the period 2010–2020, shows... / The number of people using public transport rose sharply.
- CELPIP Writing Task 2 and TOEFL Academic Discussion: one or two well-built relative clauses per paragraph show range. Don't overdo it: very long sentences with many clauses become hard to follow.
Common Mistakes
Mistake 1: Using "that" in a non-defining clause
- Wrong:
Our manager, that is from Ukraine, speaks four languages. - Correct: Our manager, who is from Ukraine, speaks four languages.
Mistake 2: Adding an extra pronoun
- Wrong:
The course which I took it was very useful. - Correct: The course which I took was very useful.
Mistake 3: "What" instead of "which/that"
- Wrong:
The job what I applied for... - Correct: The job (that) I applied for...
Mistake 4: Dangling participles
- Wrong:
Having finished the report, the computer crashed. - Correct: Having finished the report, I sent it — and then the computer crashed.
Practice Tips
- Rewrite your CV bullets. Combine two short lines into one sentence with which, who or a participle.
- Look for commas. When you read news articles, underline non-defining clauses and notice the commas.
- Check every -ing opener. When you start a sentence with a participle, ask: "Who is doing this?" The answer must be the subject.